Method of and means for producing saggars and the like



F." I. 'WOLFF. METHOD OF AND MEANS FOR PRODUCING SAGIEARS AND THE LIKE. APPLICATION FILED MAY 19, 1919.

1,337,871. I Patented Apr. 20,1920

- implication filed may To all whom it may com-cm lie it known that l, FRANKLYN d. Worm, a citizen of the United States, residing at Trenton, in the county of Mercer and State of New Jersey, have invented new and use ful lniprm'ements in Methods of and Means I for Producu haggars and the like, of which the following is a specification. v I

in the production of saggers, or nre-clay cases or receptacles which china, glass, f,

gars are usually constructed in the lie:- of open-topped pans or boxes, consisting a bottom and side Walls, so as to 1nnd protect the contained ware during g arranged in tiers, one upon another in the kiln, and to the end that they may Jithstand and properly distribute ,se heat or" the furnace, and carry their ight and that of their contents, without (to permit the damaging access and other fumes) and scaling or it is necessary that there be a subeven distribution of the grog ut the bottom and Walls of the An excess of grog in the bottom de ciency thereof in the side Walls rein weaxness, and unequal expansion means of a maulor otherwise on a table and (2} the forcing of the material by hydraulic, pressure or its equivalent into a die or form representing orfconforzning to the finished saggar. ln the first named method the slab having beenredueed the desiredQthick Specification of Letters Patent. fi my, 2Q

" the latter, While vpermitting the contraction due to changes of tempera-- involving leakage or the dropping of Serial No. 293,155.

ness is cut and the sides so formed are applied to a bottom of the selected dimensions, and then the structure is tired. Among the disadvantages of this method may mentioned the slowness of the procedure, the necessity for skilled labor in reducing the batch to slabs and the lack of uniformity in the thickness and variations in the density of the slab. In the second named method it is necessary to work the-material in a more fluid state, forcing the mixture into that portion of the die Which forms the bottom of the saggar and causing it thence to travel outward to form the side Walls. This procedure causes an excessive co1npaoting of the material forminfthe bottom and results in an uneven distribution of the grog for the reason that the more mobile clay advancing more rapidly than the solid particles of grog passes to the sides of the die to form the-Walls, and hence the latter contain a reduced percentage of grog.

It is the object of the present invention to simplify and reduce the cost of producing saggars of uniform density and even distribution or" the materials throughout the bottom and Walls, so as to minimize or eli1ni hate the risk. of cracking leaking or'otherwise deteriorating in use, and at the same time to produce a structure of equal or greater strength and resistance to heat and weight While being itself of less Weight than the saggar resulting trons the old methods, and of increased and substantially calculabl durability. I

To this end the composite plastic mixture, which may be of less fluidity than in the hydraulic method (supra), after. having its ingredients in the proper proportions thoroughly mixed and uniformly distributed is advanced forcibly through a condensingand reducing medium which serves to spread or sheet the same, Without disturbing the relations between the ingredients to produce a rangement.

1n carrying out the above indicated method there may be used an apparatus of which a suitable embodiment is illustrated in'the acconipanyingdrawings, it being understood, however both as to the method and apparatus suggested, that various changes in form and details within the scope of the appended claims may be resorted to without the mining of the ingredients and the sheeting or the composite material, to indicate an cii ective and practical relation therebetween.

lig. 2 is a sectional View in. detail to show the means whereby the lubricant is applied t the surface ot the composite material as o it advanced through the nozzle.

Fig. 3 is a detail view in perspective of the depth defining bar forming an element \JALU of the outlet of the nozzle.

l is a detail view of av portion of a composite sheet or ribbon as it appears after it has been advanced through and discharged from the nozzle;

5 is a diagrammatic view in perspective to illustrate the formation of a saggar from the ribbon or blank as it leaves the for, mechanism.

Fig. 6 is a perspective view of another form or saggar.

Essentially the method contemplated by the invention consists in efiecting an intimate mixture in the proper proportions, found in practice to be substantially half and half, of solid material in fraginentary form, such as fired clay, constituting a byproduct or otherwise waste'material of a pottery or similar establishment, and moist or plastic clay or its equivalent; then forcibly advancing the mixture in which the solid particlesv are evenly distributed in the mass and are held in suspension by theplastic clay forming the vehicle or binder, through a reducing and condensing medium by whiclu'without disturbing the relations between the particles of solid material and the vehicle or hinder, the streain or column is flattened progressively for ,ultimate discharge through a linear outlet in the form of a, ribbon or sheet of the required width and thickness; conveying the sheet or ribbon as thus tormed to a convenient distance froin'the outlet of the reducing medium; detaching portions or sections corresponding in dimensions respectively with the bottom and side walls of the proposed saggar; assembling the bottom and side wall sections while the material is still i in the plastic though h ghly condensed andcompacted condition; and finally firing the product thus assembled to produce a unitary structure.

hereinbefc-re indicated it is necessary t at and uniform distribution of id particles constituting the filler and consisting of fired clay or its equivalent shall be maintained throughout the procedure so as to characterize the structure at the ribbon or sheet which is the product of the reducing or condensing medium, and it is further essential that there be suficient moisture in the plastic clay constituting the vehicle or binder to afford opportunity for I a sufficient absorption thereof by the particles of filler to insure the complete expulsion of air from the pores of the latter to avoid-the possibility of blistering the subsequent firing operation, and in carrying out the initial step of effecting the required intimate mixture and association of the binder and filler it has been found satisfactory to employ the equivalent of an ordinary pug mill such as that illustrated in Fig. 1 of the drawings and which consists of the cyli'n drical body 20, axially within which is arranged the shaft 21 carrying pug knives 2-2 and provided at its lower end with a spiral blade pusher 23 which cooperates with a worm 24. ordinarily employed as the means for advancing the mixture to the ordinary pug mill outlet 25 and from which in the ordinary practice the composite plastic mass is discharged in the form of a substantially round stream or column.

In the reorganization of the ordinary pug mill to carry out the steps. ofcthe method forming the substance of this invention an extension sleeve 26 may effectivelybe disposed in communication with the said out let to form an entrance passage toa reducing and condensing nozzle-27, and in order to insure the continuous forcible advance of the composite plastic material through the nozzle, an additional wing and flight 28 may, as shown, be applied to the shaft 29 of the worm 24, to operate within the extension sleeve 26.

The passage through the nozzle is of graduated and progressively reduced cross sectional area, the conformation being progressively modified from the substantially round inlet 30 corresponding with the outlet of the pug mill to a fiat or rectilinear outlet 31 so as to insure the discharge of the composite plastic material in the form of a ribbon or a sheet having a definite width and a reduced thickness determinable by. the depth of the outlet 31 and variable by means of a bar 32 disposed longitudinally of the of the the outlet 25 of the pug mill from being backed out of the passage and into the body of the mill. in other words, the arrange ment described insures the continuous ad-' vance of the material from plane of the pug mill outlet through the extent of the nozzle notwithstanding the restraint or back pressure exerted i reby, and as the modification in the cross sectional contour of the passageway'through the nozzle is gradual and progressive, from the substantially round inlet where the mass or supply column is received to the lineal outlet where the discharge of the sheet or ribbon occurs, the mass or column is molded or transformed in such a way as to avoid any disturbance of the intimate relations between the solid and plastic ingredients consisting respectively of a filler and binder, and thus in effect PX'BS-BIVGYL'EXQ molecular arrangement which has been eliected in the mixing operation while in the body of the pug mill, with the result that the ribbon or sheet as itis discharged from the outlet of the nozzle is of homogeneous structure and is of uniform density throughout as well as being of accurately even thiclmess,'so that the bottom and side wall members of the resultant saggar contain definite and predetermined proportions of both filler and binder.

As illustrated in 5 of the drawing, after the ribbon or sheet of material is received from the nozzle a suitable length thereof as indicated at A in dotted lines is wrapped, folded or rolled around a suitable form 36 (corresponding with the contour of the rooosed sa ar to occuio T the L 22 L position shown in full lines at B, the joint at 6 being formed by pressing the edges of the plastic material together in the usual way, and the vform or mold withthe enveloping wall 13 formed by the blank of plastic material is arranged upon asection orblanlr of the plastic ribbon or sheet indicated at G in dotted lines, and after the latter has been cut around the circumference of the wall vto correspond in diameter and form thereof, as indicated at D, the material at the joint is pressed together sufficiently to cause adherence, after which the article is baked or fired, all in accordance with the usual practice heretofore substantially 'ob' v served in the formation of saggai's and equivalent receptacles.

Owing to the resistance adored by the walls of the nozzle in the condensing and reducing process it may be found desirable under some conditions to provide for the -furnishing to the surface or the advancing column of composite material a suitable the reception I oil which may be fee under pressure through the tubes 20, said cups having at their sides minute out ts the column of plastic grooving elements serve I) l in the surface of is deposi W to the inoistu not penetrate sh nels are closed a the outlet densing and reitseli upon the oi' the ducing material. lubricating surface of th discharged t sipated in the subsequent 0" product.

The invention havinis claimed as new l. The method with a plastic vancing the mass t I forming outlet to produce continuous L st or ribbon, detach' and removing from the path oi? the sheet ribbon, independent sections of pro ortioual dimensions to form the bottom a walls of the product and finally assembling and firing the s 2. The metho or" producing which consists lllllllfiilll? a fragmentary filler of solid material it -11 a plastic vehicle or hinder, bodily the l ss through a reforming and condensing to pro-' duce a continuous it t or ribbon, de-

taching ieinov ions or the sheet 1, :2 A. i a

or riboon 1S loaned, and nnally assenl m W." *1 l bung o 01m a baggie; stiuctuie ancniing the s d prodncing saggars wl a fragmentary filler o hscrbenti solid material with icie hin bodily advanc he through re i medium to form asheet or moving sections of one semblins; to asaggar structure and finally sn g the same. i

4:. The method producing saggars which llg u or ribbon, ae-

consists inking a solid fragmentary filler see a plastic b'intderihedilyadvancingthe' mass through a retorming passage to a sheet forming outlet to produce a oontinuous.ri-b-- hos-1,. Ideteohing and removing from the path of the ribbon, independent sections ofspropereionai dimensions toform the bottom and walis ofthe product and finaltyiassehibling timately mixed solid and plastic materials to a sheet by- 1forcibl i advancing .the same I imzswai.

medium, "coidinuousIy anddiitefinedieztelgr \8.;'' An apparatus for the yer-pose named having aforceieed mechanism ends redue mg nozziefor' receiving plestio materiai.

. therefrom,-,the, said nozzle havingsnternal through a proguessivlely,- modified. condensingvand reforming. assage terminating in-a lineal outlet of; uniform depth. and subsezuently detaching bottom and, Wall sections from tl'ie'sheet essemblin said sections and .1

finally firing the same."

- 'the'rnethod of producing saggarstwhich consists in mixing. a fragmentary filler of solid fmateniahwi-thia plastic vehicle or hinder, bodily advancing the mass through a reforming 'jmedin'm; to dischargethe same in the, form of a sheet or ribbon, detachin and removing sections of the sheetor ribbon,

assembling the sections to form a \saggar structure and emu firing the same.

7. The method 0 producing a homogeneous ribbon of composite mate rial having solid particles 1n suspenslon in a plastic vehicle which consists in forcibly advancing the mass after mixture through a, progressively modified reducing and condensing channel n forming elements and associated lubricant feeding means;

-93 In: the production oi seggars ato'r use 12 firing pottery iehdtthe 1ike,;and wherein the walls andbotto'm' are eomposedof a substan tl-aily .fired mixture of ,appiastlc vehicle er binder in which is incor 'orateda fra mene wry-filler irfxsaiid; meteriaL-and wherein uniform distribution of the fragmentary r' :of the. .Welis fillerf throughout the bed; bottom is desired, the method of iornd'ngr sheet orstrip' ifrceeqtvhieh seid walisgeed bottom maybe: cnt wwhich consists in theronghlyw mixing said vehicle or; binder and filler to secure the said uniform distribution of the latter throughout the massand then advancing the mass, under pressure, throrlgh aprogressivelymodified shape transforming passage to e transversely elongated outlet of a depth determining the thickeess of the sheet or ribbon.

' n In testimony whereof I aflix mysignature. A

FRANKLYN J. WOLFE. 

